Conventional recreational vehicle cover is a long rectangle box with a faced down opening and is made of rain-proof and sun-resistant material. For convenient to tie to the recreational vehicle, the bottom edge of the front wall and the rear wall of the cover are respectively disposed with elastic band, the external surfaces of the right and left walls are respectively disposed with a row of laces extending downward, the upper ends of each lace are sewn with a triangle reinforcing piece to a correspondent position of the centre of the external surface of a corresponding wall. However, as the recreational vehicles are taller and longer than normal cars, it is difficult to assemble the cover to the recreational vehicle compared to the assembly on a normal car wherein a user could easily assemble the cover just stand besides the normal car. When assembling the recreational vehicle cover, it is needed to be rolled along its length direction and then be spread out by one person on the vehicle roof; there further needs another person lower to cooperate with the person on the vehicle roof and set each wall of the cover in order to make them respectively covers the corresponding side of the recreational vehicle. Finally, each pair of the corresponding laces in the right and left sides of the recreational vehicle cover is tied together. With the elastic bands at the lower ends of the front wall and rear wall of the cover and the laces, the recreational vehicle cover is tightly fixed to the recreational vehicle. When dissembling the recreational vehicle cover, it needs one person to climb on the vehicle roof for lifting the front wall or the rear wall of the cover, rolling the cover and then throwing it to the ground.
However, people are not satisfactory with the conventional manner that is climb on the vehicle roof, spread the cover or roll the cover. The manner is hard and dangerous; and expected to be modified. It is desired that user could just stand by the car to assemble or dissemble the recreational vehicle cover.